Late Changxingian (late Dorashamian) ammonoids are known only in three regions of the world: South China (Chao, 1965; Zhao, Liang, and Zheng, 1978; Sheng, 1989), Transcaucasia (Zakharov, 1985, 1986, 1992; Zakharov and Rybalka, 1987; Kotlyar, 1991), and South Primorye (Zakharov and Pavlov, 1986; Zakharov, 1987, 1992). Until recently, their presence in the last two areas had been confirmed only by rare finds.
This chapter comprises excerpts from a lecture presented at an international conference on the Carboniferous–Jurassic strata of Pangaea (Zakharov and Oleinikov, 1993), with some additions. We now have information on two late Changxingian ammonoid complexes discovered in the Primorye region: The first and most representative complex was found on the right bank of the Partizanskaya River (1.0–1.5 km northeast of the railway station of Vodopadnaya) in 1992. The second, comparatively more scanty, was recognized on the left bank of the Artemovka River some years ago (Zakharov, 1987, 1992).
Occurrences of late Changxingian ammonoids in Primorye
In descending order, the sequence of Permian–Triassic sediments in the section at Vodopadnaya is as follows:
Peschanka River Suite (Lower Norian)
8. Dark grey mudstone, coal argillite, and grey sandstone (∼5 m): Yields plant remains identified by S. A. Shorokhova and E. B. Volynets as Ctenis ex gr. sulcicaulis (Phillips) Ward, Taeniopteris spathulata Oldham and Morris, Pseudoctenis ex gr. mongugaica Prynada, Podozamites cf. kiparisovkensis Srebrodolskaya and Shorokhova, P. ex gr. lanceolata (Li and Hsu) Braun, Elatocladus ex gr. cephalotaxoides Florin, Cycadocarpidium sp., and Pachipteris (Thinnfeldia) sp.
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